Perhaps you should try some spelling variations:
doan manh » doan minh, hoang manh, tran manh
nam thuc » nam thuoc, nam thu, nam tu
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
manh va » hanh va, anh va, minh va
ca viet » va viet, hoa viet, san viet
co viet » so viet, o viet, hoc viet
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky nang x hoi. hieu ve ((nam thuc) or (am thuc)) doan manh va ((ca viet) OR (co viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky nang x hoi. hieu ve ((nam thuc) OR (am thuc)) doan manh va ((ca viet) OR (co viet))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky nang x hoi. hieu ve ((nam thuc) or (am thuc)) doan manh va ((ca viet) OR (co viet))*".